Highway crossing warning system



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INVENToR. .John U. Elder.

HIS ATTORNEY United States Patent HIGHWAY CRGSSING WARNING SYSTEM John C. Elder, Penn Township, Allegheny County, Pa.,

assignor to Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Filed Aug. 20, 1957, Ser. No. 679,167

Claims. (Cl. 246-2) My invention relates to a highway crossing warning system. More particularly my invention re-lates to a warning system for protection of highway traffic moving over a highway which crosses one or more tracks in a railway car classification yard incorporating an automatic switch control system.

In a classification yard where a highway crosses one or more tracks, several cars or cuts of cars may be simultaneously in the track sections which comprise the approach Warning track stretch for actuation of a warning system for the highway crossing. One or more of these cars or cuts may be destined for a route crossing the highway land others may not. Because of these variable factors itis not economically justifiable to provide a conventional type approach warning system for the crossing, due to the necessary additional circuitry for the prevention of its operation when cars or cuts of cars are present in the approach warning track stretch but none are destined for a route over the crossing. The circuitry for the proper operation of the warning system would be relatively involved and the amount of apparatus used prohibitive under these conditions.

Automatic switch control systems for railway car classification yards are often controlled by route storage systems which provide for the storing of the routing for successive cars or cuts of coupled cars which are to pass over a hump and move under the influence of gravity to the various tracks in the classification yard. The route identity or description for each cut of cars is usually stored by the operator of the yard selecting from a bank of push buttons the final classification or storage track number to which the particular car or cut is to travel. Such route identities are stored in an initial storage unit which is comprised of a series of storage banks until each corresponding car or cut is ready to move over the first switch-in the yard, after which the route identity for each cut is transferred from the initial storage unit to the storage banks for the next switch at which the cut Will arrive, and thence successively to the storage banks for any other switches in the route as the cut of cars progresses towards its designated track. These route identities may at various times be termed route descriptions, route storages or switch storages. The various switches are controlled automatically by the route identity or switch storage in the route storage system as the storage is transferred from one bank to` the next by lthe progress of the cut. Such systems and their automatic operation are well known in the art.

Automatic switch control systems for railway car classication yards are also usually supplemented by means for manual control of the switches for use in the event itis desired or necessary, due to repairs to the systern or some other reason, to control the switches individually and independently ofthe automatic control system.

One object ofV my invention is to provide a highway crossingzwarning system for a highway crossing one or more tracks in a railway car classification yard having ICC an automatic switch control system of the route storage type, by using the minimum of apparatus. To accomplish this objective my invention makes use of the route storage portion of the automatic switch control system to transfer destination identities or descriptions along with each cut of cars as they proceed, similarly as the route identities for each cut is moved through the storage banks of the automatic switch control system.

Other objects and characteristic features of my invention will become apparent as the description proceeds.

I shall describe one form o-f apparatus embodying my invention, and shall then point out theV novel features thereof in claims.

In the accompanying drawings,

Fig. 1 is a partly diagrammatic, partly schematic View of a railway car classification yard equipped with an automatic switch control system including the apparatus of my invention.

Figs. 2a, 2b, and 2c, when placed side by side in the order named with Fig. 2a on the left, show diagrammatically the control circuits embodying the features of my invention when applied to the automatic switch control system for the yard shown in Fig. 1.

In each of the drawings similar reference characters refer to similar parts of the apparatus.

It should be pointed out at this time that a suitable source of energy for the control circuits of Figs. 2a, 2b and 2c is provided, this source being preferably a battery of proper voltage and capacity. For thefsake of simplicity this power source is not shown in thedrawings, but its positive and negative terminals are identified by the reference characters B and N, respectively.

Also, the contacts of relays which are slow acting are identified by the use of vertical arrows thereon, the direction of the arrows indicating the direction in which the relays` are slow operating.

Referring now to Fig; l, a railway car classification yard is shown having seven classification or storage tracks. Cuts of cars enter this yard from the hump over the single track at the left ofthe drawings. This single track diverges through thevarious switches into the seven storage or classification tracks which are numbered from 1 to 7 as clearly shown on the drawings. The cuts of cars being classified are rou-ted into the selected sto-rage tracks by the variousV switches. In moving over the switches the cars being classified always` move in a facing point direction, andY for such moves each switch is considered to be in its normal or reverse position accordingly as the cars are routed into the left-hand of right-handtrack, respectively, by the switch. In Fig. 1 all switches are shown in the normal position.

A highway is shown crossing classification track 7 and flashing light signals are shown for providing a warning indication to vehicle traffic using the highway over that track. It is to be understood that my invention may be applied to any size classification yard, the highway may cross more than one classification track in the yard and any type of highway crossing warning device may be used. However, for purposes ofsimplicity only a smalll classification yard is shown.

In the yard arrangement shownin Fig. 1 the switches are shown in the simplest manner possible. The switches are designated by the reference character SW prefixed by a hyphenated number which indicates the storage tracks to which that switch leads. For example, the initial switchA in thev yard is designated by the reference character 1-7SW to indicate that this switch controls the routes to storage tracks 1 to 7, inclusive, or all of the tracks shown. As a further example switch 5-7SW controls the routesto storage tracks 5, 6 and 7. The significance of the reference characters designating the remaining switches is believed obvious from this description.

Each switch in the classification yard except switch S-SW is provided with a power operated switch movement which controls the positioning of the switch points to their normal or reverse positions. These switch movements are not shown in Fig. 1 and any well known type of switch movement may be used. The switch movements are controlled to operate the associated switches to the desired position according to the preselected routes which exist through the automatic switching system ernbodying my invention and with which the yard is equipped. The switch movements may also be controlled to operate the associated switches to the desired positions by means of a manual control lever for each individual switch. Switch -6SW is a hand throw or hand operated switch and is identified as such by the reference character HT.

Each switch in the classification yard shown except switch 5-6SW is also provided with a detector track section. These track sections are set off by insulated joints which are shown in a conventional manner by lines at right angles to the conventional single lines representing the railroad tracks. The detector track sections are designated by the reference characters T prefixed by a hyphenated number corresponding to the similar number associated with the switch reference. For example, track section 1-7T is associated with the initial switch in the yard, switch 1-7SW. In addition to these detector track sections approach track sections are provided for the track between each detector track section in the route leading to the highway crossing. These approach track sections are designated by the reference characters APT prefixed by a hyphenated number corresponding to the similar number associated with the detector track section and switch next in advance. For example, approach track section 3-7APT is associated with detector track section 37T and switch 3-7SW. These approach track sections are used to provide continuous detection of cuts of cars destined for the route over the highway. It is to be noted that no such track section is provided between detector track sections 1-7T and 2-7T as the operation of the highway crossing warning system is not initiated until a car enters track section 2-71". This starting point is shown in Fig. 1 by an arrow with the designation start.

Two additional track sections, HXT and APHXT, are shown in Fig. 1. Track section HXT spans the highway and provides the positive ringing section usually provided for highway crossing warning systems, and track section APHXT is an approach section for any train movements which may move towards the hump from storage track 7, for example, an engine during trimming operations.

Each of the track sections is provided with a track circuit which includes a power source, the rails of the section, and a track relay. In the conventional showing of Fig. 1, only the track relay connections to the rails are shown, these being indicated by the dotted lines between the single line track and the symbol for the correspondlng track relays. Each of the track relays is designated by the reference character TR or APTR prefixed by a hyphenated number corresponding to that of the track section. As an example, track relays 3-7TR and 3-7 APTR are associated with track sections 3-7T and 3-7APT, respectively. Any well known type of track circuit may be used in the track sections and, for the purposes of this description, it will be considered that the track relays are normally energized when no car occupies any portion of the associated track section. These track relays are also shown in Figs. 2a, 2b or 2c in connection with the detailed circuit arrangements but the showing in this figure is of the relay winding and contacts only, and it is to be understood that the relays with identical designations in both Figs. 1 and Figs. 2u, 2b or 2c are the same relays.

As previously set forth there is also shown in Fig. 1 a hand throw switch designated 5-6SW and having a reference HT to distinguish it from the power operated switches shown. The power operated switches and the hand throw switch are equipped with circuit controllers each of which is designated in Figs. 2b and 2c by the reference character SWC prefixed by the hyphenated number of the switch with which it is associated. Further explanation concerning the hand throw switch will be set forth later in this description.

Fig. 1 also includes a flow chart to illustrate the progression of the route identities or switch control storages in the automatic switch control system as they are transferred throughout the circuit arrangement to control the Various switches along the preselected routes. The progression path is here illustrated as a dot and dash line with t-he lettered blocks representing the route storage banks associated with the various switches. For purposes of simplicity each switch is shown to have an associated storage unit with but one storage bank but it is to be understood that the storage units may consist of as many storage banks as desired. Therefore, as will be more fully explained hereinafter, the storage unit associated with initial switch 1-7SW is assumed to include more than one storage bank but only the final storage bank A is shown as this is sufficient for an understanding of my invention.

ln general, the route identities are initiated in the track selection panel or push-button bank and progress through the initial storage banks as described in the copending application for Letters Patent of the United States, Serial No. 355,281, filed May 15, 1953 by Benjamin Mishelevich for the Automatic Control of Railway Classification Yard Track Switches, now Patent No. 2,863,991, granted December 9, 1958. From the initial storage banks each route identity finally progresses into final storage bank A associated with the initial switch in a manner described in said copending application.

From the storage bank A associated with the initial switch each route identity is transferred, as the corresponding cut of cars progresses through the yard, to the storage unit for the switch next in advance that will be traversed by said corresponding cut. This transfer of route storage is described in the copending application for Letters Patent of the United States, Serial No. 592,198, tiled June 18, 1956, by John R. George et al. for the Automatic Control of Railway Classification Yard Track Switches, now Patent No. 2,863,992, granted December 9, 1958. For example, in the yard layout as shown in Fig. 1 of my application, for a cut of cars being routed to track 3, the route storage would be initiated in the push-button bank and eventually transferred into final storage bank 1-7A for switch 1-7SW. As the corresponding cut occupies detector track section 1-7T, this route storage is transferred into storage bank 2-7A for switch 2-7SW. When this storage has thus been transferred, switch 2-7SW is properly positioned, in this instance moving to its reverse position if not already so positioned. When the said cut of cars occupies track section 2-7T, the route storage is transferred to storage bank 3-7A associated with switch 3-7SW. Switch 3-7SW is then positioned normal, if not already so, to route the cut to track 3. When the cut eventually occupies detector track section 3-7T the route storage in bank 3-7A is cancelled. The route storages in the preceding banks for this cut are cancelled each time the storage is transferred to the next storage bank. The transfer of storages along other routes is similar and progresses as shown by the said flow chart. v

Referring now to Figs. 2a to 2c, inclusive, these drawings when arranged in consecutive order from left to right show the circuit arrangement for control of the highway crossing warning system for cuts 0f cars moving from the hump towards the crossing and destined for storage track 7. The circuit arrangement as shown in cuits of my invention. .The apparatus of the automatic switch controlsyste'rn isshown only so far as necessary for a clear and complete understandingof my invention as it forms no part thereof. It is suffcientto point out at this time thatthe relays with AT and AD suxes `shown in Fig. 2a are controlled ina manner identical to the relays with similar sutlixes shown'in the previously mentioned "copending application, Serial No. 592,198. For example, relay 2-'7AT is the storage transfer relay `for storage'bank 2-7A and relay 2-7AD is "the storage detector relay for that storage bank. The operation of such relays will be more fully explained hereinafter.

The track selection panel for the classification yard, by which the operator `selects the proper storage or classiiication track for each cut of cars moving over the hump, is represented by the push-buttons `on the upper left-hand portion of Fig. 2a. :Each'of these six push-buttons is designated by a reference character PB prefixed by a number 'corresponding to the classification track with which the particular button is associated. For example, the depressing of push-button -1PB establishes a storage of the route to classiiication track 1, while the depressing of push-button 2 establishes a similar storage to classification track 2. The Vproper route for each cut of cars is selected by the operator pushing, in the same sequence that the cuts move over the hump, the correct push-button 4for the destination of each cut.

There is illustrated in Fig. 2a in a conventional manner the windings only of the necessary number of usual switch storage relays 1-7A1 through 1-7A5, inclusive. These switch storage relays are energized in different combinations as determined by the operation of the various route 'selection push-'buttons as previously set forth. However, the circuit arrangements by which these relays are energized are not part of my invention, and it may be vassurnedthat these circuit details are identical to the circuit arrangement by which the corresponding relays 1-6A1WR, 1-6A2WR etc. shown in the aforementioned copending application, Serial No. 355,281, are energized.

Reference is made to this copending application for a complete description and showing of the energizing circuits for these relays. For the sake of simplicity, the energizing circuits for these relays are shown in a conventional manner by the dotted lines inside the dot dash rectangle.

For purposes of the present description it is suicicnt to state that in the storage bank 1-7A there must be one switch storage relay for each switch in the route having the maximum number of track switches. In the yard illustrated in Fig. l, the maximum number of track switches in any route is live (discounting the hand throw switch 5-6SW). Thus five switch relays are required 1n storage bank 1-7A associated with switch k1-7SW. It will be assumed that when a switch must be operated to its reverse position for a selected route, the corresponding switch storage relay in whatever route has been selected will be energized in the combination for Ithat route. If a switch must be operated to its normal position for a selected route, the corresponding switch storage relay will remain deenergized in the combination for that route. By referring to Fig. l it will be seen that the route to track 3 passes over switch 1-7SW normal, switch Z-7SW reverse and switch 3-7SW normal. Thus, for the route to that track, switch storage relay 17A2 only need be energized and the conventional dotted line circuit connections shown in the aforesaid portion of Fig. 2a are so shown that a circuit for energization of relay 1-'7A2 only is prepared upon depressing the track selection push-button for track 3. Similarly, the route to track 7 passes over all the switches, switch 1-7SW in its normal position and the remaining switches in their reverse positions. Thus, the switch storage relays 1-7A2, 1-7A3, 1-7A4 and 1'-7A5 must be energized to establish the route to track 7. The

conventional dotted line connections shown in Fig. 2q are shown so connected that the operation of track selection 'push-button 7PB eventually'energizes each of the'necessary named relays.` 4 K Y vIn accordance with'my invention there is shown in the 'initial storage bank 1-7A in Fig. 2a an additional relay V1-7AX. This relay is a destination description or identity 'relay and is'energized in a similar manner to the switch storage relays aswill be set forth later in this description. This relay is energized whenever any track other than tracks 1 and 7 are selected by the operation of a track v'selection push-button. Thus, relay 1-7AX must be energized whenever any switch 2-7SW through -5-7SW is to be positioned 'normal'because of the route selected by the operation yof Aa track selection push-button. In

"other words the destination description Arelay will remain dee'nergized when 'a track destination requiring a route over the highway crossing is selected by the operator depressing the track selection push-button for thel route to track 7. inthe yard shown invFig. l'this would 'be when 7PB is operated. By referring once again to the conventional dotted li'ne connections shown in Fig. 2a it will`be seen that a connection is made for energizing 1-7AX except when 7PB or 113B is depressed.

It is not necessary'to energize relay 1-7AX when stor- "age tr'ack'l is' selected as a destination, although the desti- 'nation is other than over the road crossing, because a cut of cars proceeding from the hump to storage track 1 will not occupy any of the track sections which are inclined in the yapproach warning track stre-tch for the crossing. As previously pointed out the starting point for actuation of the highway crossing warning system is track'section 27T as shown in Fig. 1.

Storage detector relay 1-7AD, the operating winding only of which is shown in Fig. 2a, is `energized when a storage from the last of the initial storage banks is transferred into nal storage bank 1-7A. Relay 1-7AD is retained in an energized condition until a storage in its associated storage bank 1-7A is transferred into storage bank 2-7A. As previously discussed relay 1-7AX is energized in a manner similar to the switch storage relays. As shown in Fig. 2a, the closing of contact a of the storage detector relay 1-7AD completes the circuit for energizing the proper switch storage relays, and the destination description relay as well if that relay is to be energized. As also previously pointed out, the circuits for the control of the storage detector relay AD for the initial switch in ayard are shown in detail in the above referred to copending application, Serial No. 592,198.

Fig. 2a also shows similar destination identity yrelays 27AX, '3-7AX,' 4-7AX and 5-7AX associated with the storage banks for switches 2-7SW, 3-7SW, 4-7SW and 5-7SW, respectively. The switch storage relays in these banks are not shown since they and their control circuits form no part of my invention.` It is sutcient to point out that the switches in the yard will be controlled to the. correct position for a route associated with a cut of cars, as the cut progresses through the yard, in the manner described in the last cited copending application.

For an example, it will be assumed that the hump operator selects track 3 as the destination for a cut of cars. By referring to Fig. 2a it is apparent that operation of route` selection push-button 3PB prepares for the energization of relays 1-7A2 and 1-7AX, the energization of these relays being completed when relay 1-7AD closes its front contact a to complete the energizing circuits for the relays 1-7A2 and 1-7AX. Relay 1-7AD closes its front contact when the switch storage for the cut of cars finally is transferred into-storage bank 1-7A as previously set forth. Relay 1-7AX is provided with a stick circuit over its own yfront contact a to retain thatrelay energized as long ias relay 17AD vremains energized. Relays l-'ZA through 1-7A5 have `similar stick 'circuits which are not shown in Fig. l2a but which are identical to those for corresponding "switch -sforaige 'relays 3-9A1, 3-9A2, etc.,

baresi shown in the aforementioned copending application,

Serial No. 592,198.

ln the route to storage track 3 only switch 2-7SW need be positioned reverse and, therefore, this switch being the second in the route, only relay 1-7A2 need be energized to store the correct switch storage in 1-7A storage bank. Relay 1-7AX must be energized at this time because the cut of cars for which track 3 is the destination will not move over the highway crossing.

As the route identity for control of switches for a route to track 3 is transferred through the storage banks the destination identity is similarly transferred, that is, by the operation of the relays AT and AD. When the previously mentioned cut of cars enters track section 1-7T, energy is applied to the winding of relay 2-7AT for energization of that relay. The energization of relay 27AT causes energy to be applied to relay 2-7AD and that relay is energized if there is no storage in storage bank 2-7A. The energization of relay 2-7AD removes energy from relay 1-7AD and that relay is deenergized. The deenergization of relay 1-7AD restores storage bank 1-7A to normal condition and in condition to receive a storage for the next cut of cars. The deenergization of relay 17AD also removes energy from relay 2-7AT and that relay is deenergized. Relay 2-7AD, however, remains energized until the storage in storage bank 2-7A is transferred into the next storage bank 3-7A by the occupancy of track section Z-7T by the cut of cars and in a manner simillar to that just described. Since switch 3-7SW is the last switch in the rou-te to track 3, relay 3-7AD associated With 3-7A storage bank is deenergized when the cut of cars enters track section 3-7T. Relays 4-7AT and 4-7AD, and 5-7AT and 5-7AD are controlled in a manner similarly to that just described for relays 27AT and 2-7AD, when the route associated with a cut of cars is also over switches tl-78W and 5-7SW. For a detail description of the operation of relays AT and AD, reference is made to the above referred to copending application, Serial No. 592,198.

As stated above a destination identity, for each cut of cars moving over the hump and not destined for track 7 over which the highway crosses, is transferred through the storage banks in an identical manner as the switch control storages are transferred. However, no destination identity is required for a cut of cars if the destination of the cut is storage track 7 or over the highway crossing. As previously mentioned neither is a destination identity required for a cut of cars if its destination is storage track 1 as no crossing warning circuits can be actuated by a cut moving over the track section 1-7T to storage track It. The operation of the destination identity relays will be described in more detail in several specific examples to follow.

In Figs. 2b and 2c, are shown a series of repeater relays or rst control relays, and repeater stick relays or second control relays designated by the reference characters having the suffixes XPR and XPSR, respectively. Each of these reference characters are prefixed by a hyphenated number designating the destination identity relay with which they are associated. This hyphenated number also agrees With the switch and detector track section with which the relays are associated. For example, relays 2-7XPR and `27XPSR are associated with destination identity relay 2-7AX, switch 2-7SW, -and detector track section 2-7T. The repeater relays XPR are controlled in part by their associated destination identity relays and detector track section relays. The repeater stick relays XPSR are controlled in part by their associated switch circuit controllers, their associated detector track relays, their associated repeater relays and, in most instances, by the approach track section relay for the approach track section next in advance. The

`operation and function of these repeater relays and repeater stick relays will be discussed in detail hereinafter. Contacts a of switch circuit controllers 2-7SWC,

2c, are used in the control circuits of the repeater stick 3-7SWC, 4-7SWC and 5-7SWC, shown in Figs. 2b and relays 2-7XPSR, 37XPSR, 4-7XPSR and 5-7XPSR, respectively, as mentioned above. These contacts are shown in their closed positions as they would be when their respective switches 27SW, 3-7SW, 4-7SW and 5-7SW are in their normal positions. The function of these contacts in the circuit arrangement will be set out in detail later.

In Fig. 2b there are shown directional stick relays ESR and WSR which are utilized for prevention of operation of the highway crossing warning system when a cut of cars or a trimmer engine has already traversed the cross ing and is receding therefrom, similarly as in conventional highway crossing warning systems involving two direction running in single track railway territory. These relays also are controlled in the same manner as relays in conventional highway warning systems.

Fig. 2b also shows a crossing warning relay XR which controls the operation of the crossing warning devices. The control circuit for operation of these devices is illustrated in Fig. 2b in a conventional manner by the dotted line showing a circuit from battery terminal B over back contact a of relay XR and captioned to crossing warning devices. The remainder of the circuits for the operation of the warning devices forms no part of my invention but it is to be understood that any type of such device may be used along with the circuitry necessary for operation of the devices. The devices, for example, may be flashing light signals as shown in Fig. 1 of my drawings, crossing gates, or automatic flagrnan or wig-wag signals. Relay XR is normally retained in an energized condition and the detailed operation of this relay will be described later in this description.

At the bottom of Fig. 2c are shown, in partial form, the control circuits for switches 4-7SW and 5-7SW, respectively. Also shown are a manual control lever 5-7MC and a lever repeater relay S-7LRPPSR. These circuits, lever and relay are utilized to provide alternate operation under special conditions and the operation thereof will be fully covered by description later in this specication.

In Figs. 2a through 2c all apparatus is shown in its normal condition as it is when no storages have been initiated, no cars are moving through the yard, and all switches are in their normal positions. I will now assume that a lirst cut of cars, which is to move to classification track 2, as shown in Fig. l, moves over the hump. The operator depresses track selection push-button ZPB and thus yassociates with the cut of cars a track 2 destination identity. This identity or storage will eventually be stored in storage bank l-A or the A bank for switch 1-7SW. By examination of the dotted circuits in Fig. 2a it `will be apparent that the depressing of push-button 2PB will prepare an energizing circuit for destination identity relay l-'IAX only in the 1-'7A storage bank. None of the switch storage relays become energized bccause the route to classiiication track 2 is through switches 1-7SW and Z-SW in the normal position.

Upon picking up of relay -7AD as previously de scribed, a circuit through the winding of relay 1-7AX to battery terminal N is completed through front contact a of relay 1-7AD, and relay l-7AX therefore picks up. Relay ll-7AX is subsequently retained in its picked up condition by a stick circuit which may be traced from battery terminal B through front contact a of relay 1-'7AX, winding of relay l-7AX, and front contact a of relay 1-7AD to battery terminal N. This stick circuit is similar to the stick circuits provided `for switch storage relays 1-7A1 through l-I'AS and it is apparent that relay 7AX is operated in a manner similar to the operation of the switch storage relays. 4

Upon the iirst cut of cars advancing from the hump and entering track section 1-7T, the switch storage and the destination identities associated with that cut are "transferred into storage bank -27A associated withswitch Z-7SW. This transfer is completedupon the energization` of relays 2-7AT and 2-7AD as previously described. Since the Yroute into classification track 2 is through switch 2-7SW in its norm-al position, as previously pointed out, only the destination identity relay 2,-7AX vwill 'be energized by the picking up of relays 2-7AT and 247AD. Thisenergizing circuit may be traced from battery terminal B through front contact b of relay 1,-7AX, front contact a of relay 2-7AT, winding of relay 2-7AX, andfront contact a of relay Z-AD to battery terminal N. Relay 2-7AX is subsequently retained in its energized condition by a stick circuit 'from battery terminal B through front contact a of relay 2-7AX, winding of relay 2-7AX, and front contact a of relay 2-7AD to bat- .tery terminal N.

The vcompletion of the transfer of Vstorages from storage bank 1-7A into storage bank 2-7A allows storage bank 1-7A to be restored to its normal condition and the operator may now store a route for a second cut of cars that will move over the hump, this cut being assumed for purposes of this description to be destined for classification track 3. This storage is made by depressing vof rtrack selection push-button 3PB. The route to this track .requires switch -7SW to be in the normal position, switch 2-7SW to be reverse and switch 3 7SW to be'normal. This route being other than over the highway crossing also requires a destination identity to prevent operation of the highway crossing warning system. By examination of the dotted portion of the circuits in Fig. 2a it is apparent that operation of the track selection push-button SPB for the second cut of cars prepares circuits for energization of relays 1-7A2 and i-7AX only and these relays become energized by the energization of relay 1-7AD and consequential closing of front contact a of that relay.

The entering of the rst cut of cars into track section 1-7T causes a transfer of the route storage for that cut and the energization of relay 2-7AX as previously described. By referring to Figs. 2a and 2b it may be seen that the energization of relay 2-7AX completes a pick-up circuit for relay 2-7XPR. This circuit may be traced from battery terminal B through front contact c of relay 2-7AX, conductor 5t), and winding of relay 2-7XPR to battery terminal N. The energization of relay 2-7XPR closes a stick circuit to relay 2-7XPSR which may be traced from battery terminal B through front contact b of relay 2-7XPR, front contact a of relay 2-7XPSR, and winding of relay 2-7XPSR to battery lterminal N.

Relay 2-7XPSR is normally retained in an energized condition by a multiple control circuit which may be traced from battery terminal B through front contact a of track relay 2-7TR, or through contact a of switch kcircuit controller 2-'7SWC which is closed when switch 2-7SW is in its normal position, contact a of relay 3-7APTR, and winding of relay Z-XPSR to battery terminal N. Contacts a of relay 2-7TR and switch circuit controller 2-7SWC also are used in a multiple stick circuit for relay 2-7XPSR which may be traced from battery terminal B, said contacts a of 2-7R and y2-7SWC, front contact b of relay 2-7XPSR, and winding of relay 2-7XPSR to battery terminal N. The operation of these last traced control and stick circuits will be explained as this description proceeds.

Relay 2-7XPR is also provided with a stick circuit which may be traced from battery terminal B through back contact a of relay 2-7TR, front contact a of relay 2f-7XPR, and winding of relay 27SPR to battery terminal N. The function of this stick circuit will also be made clear later in this description.

As previously set forth relay XR is normally retained in an energized condition by-a circuit which, by referring tolfigs. 2b and 2c, may be traced from battery terminal B through front contact a of track relay APHXTR, front -contact c of relay 2-7XPSR, front contact c of relay -3-7XBSR, conductor 55, front contact of 'relay 4-7XPSR, front contact c of relay 5-'7XPSR, 'conductor 57, front contact a of track relay HXTR, Aand winding of relay XR to battery terminal N. Relay XR may also be energized by twocircuits which are for prevention of operation of that relay when a receding move isl made away from the crossing in one or the other directions. The operation of these latter circuits will be discussed below.

Assuming that the first cut of cars now enters track section 2-7T, the vpreviously traced control and stick circuits to relay Z-7XPSR through front contact a lof track relay 2-7TR are opened by the deenergization of this latter relay. However, relay 2-7XPSR is retained energized by the previously described stick circuits through contact b of relay 2-7XPR and through contact a of switch circuit controller 2-'7SWC- The control circuit for relay 2-7XPSR through contact a of circuit controller 2-'7SWC also remains closed at this time. Relay 2.--7XPSR remaining energized and, maintaining its contact c closed in the previously described control circuit of relay XR, no highway crossing warning is given at this time although, upon entering track section 2-7`I`, the cut of cars is within the approach warning track stretch. lt is apparent, however, that the cut being destined for track 2, it will not pass over the highway and no crossing warning should be given.

The entrance of the irst cut of cars into track section 2-7T cancels the storage in storage bank 2-'7A and another storage may now be transferred into that storage bank.

I will now assume that, when the first cut of cars enters track section 2-7T, the second cut enters track section ll-7T. The entrance of the second cut into track section l-'Z'T causes a transfer or" the storage in storage bank 1-7A to storage bank 2-7A in the same manner as when the first cut of cars entered track section 1-7T. However, the second cut of cars being destined for track 3, a switch storage for cont-rolling switch 2-7SW to the reverse position is made. This storage will have no effect on the position of switch 2-7SW at this time as this switch is locked due to deenergization of track relay 27TR by the presence of the first cut of cars in track section 2-7T. The locking of the switches in this manner is the usual detector locking employed in such installations and is shown in detail in said copending application, Serial No. 592,198.

I will now further assume that the operator depresses track selection push-button 7PB for a third cut of cars which is destined for storage track 7, the route to which leads over the highway crossing. This storage may now be made as the transfer of the storage for the second cut of cars to storage bank 27A left storage bank 1-7A empty of storages. The route to track 7 requires that switch l-7SW be positioned normal and the remaining switches reverse. The depressing of push-button '715B will therefore, energize switch storage relays 1-7A2, l-7A3, l-7A4 and 1-7A5. Relay 1 7AX is not energized at this time as a crossing warning for this cut of cars is to be actuated.

When the first cut of cars vacates track section 2-7T, switch 2-7SW will be unlocked by the picking up of track relay Z-'TR and the reverse switch control storage for switch 2-'7SW can take eiect. Switch 2-7SW will, therefore, be positioned reverse at that time. It should be noted at this time that, when the rst cut of cars enters track section 2-7T and the destination identity in storage bank 2-7A thereby cancels, relay 2-7AX is deenergized and opens at its contact c the pick-up circuit for relay 2-7XPR. However, relay Z-'XPR is retained energized by the previously described stick circuit through its ownfront Contact a and back contact a of track relay 2-7TR. The stick circuit to relay 2-'7XPSR through its Yown front contact aand front contact b of relay 2=7XPR 11 :is therefore also maintained and no actuation of relay .XR results from the deenergization of relay 2-7AX upon 'the tirst cut entering 2-7T and cancelling the storage in :storage bank 2-7A.

When the storage for the second cut of cars transfers into storage bank 2-7A, relay 2-7AX is again energized :and reestablishes the pickup circuit for relay 2-7XPR `which in turn reestablishes, through its front contact b, the stick circuit to relay 2-'7XPSR. Switch 2-7SW being positioned reverse the previously described control and ,stick circuits to relay 2-7XPSR through contact a of switch circuit controller 2-7SWC will be opened. Relay Z-7XPSR, however, is retained energized by the stick circuit through its own front contact b and front contact a of relay 2-7TR and by the stick circuit through its own front contact a and front contact b of relay ,2-7XPR.

I will now assume that the second cut of cars enters track section 2-7T. This movement will cause a transfer iof the storages in storage bank 2-7A to storage bank .3-7A and a cancellation of the storages in storage bank 2-7A. This second cut being destined for track 3, only relay 3-7AX in storage bank 3-7A will be energized. The cancellation of the storages in bank 2-7A due to the deenergization of track relay 2-7TR by the entrance of the second cut of cars into track section 2-7T causes relay 2-'7AX to drop and open the pick-up circuit to relay 2-7XPR at contact c of relay 2-7AX. The deenergization of track relay 2-7TR also opens at its front contact a the stick and control circuits to relay 2-7XPSR. Relay 2-7XPR being provided with a slow release feature will not drop upon the opening of contact c of relay 2 7AX as its stick circuit over its own front contact a and back contact a of relay Z-ITR will be established either prior to the opening of contact c of relay 2-7AX or so quickly thereafter that the slow release feature of relay 2-7XPR will bridge the open circuit period between the dropping of relay 2-7AX and the closing of back contact a of relay 2-7TR. The opening of the previously stated stick and control circuits to relay Z-7XPSR by the opening of front contact a of relay 2-7TR is therefore immaterial at this time and relay 2-7XPSR will remain energized by the stick circuit over front contact b of relay 2-7XPR. The control circuit to relay XR is, therefore, again retained closed and no actuation of the highway crossing warning system is initiated upon the entrance of the second cut of cars into track section 2-7T.

When the second cut of cars enters track section 2-7T as stated, relays 3-7AT and 3-7AD Will be energized as previously described and the storages in storage bank 2-7A will be transferred to storage bank 3-7A. Relay 3-7AX only is energized at this time as the second cut of cars, as previously stated, is destined for track 3 or through switch 3-7SW in the normal position. Relay 3-7AX is energized by a circuit that may be traced from battery terminal B through front contact b of relay 2-7AX, front contact a of relay 3-7AT, winding of relay 3-7AX, and front contact a of relay 3-7AD to battery terminal N. Relay 3-7AX is retained energized by a stick circuit that may be traced from battery terminal B through front contact a of relay 3-7AX, winding of relay 3-7AX, and front contact a of relay 3-7AD to battery terminal N. It is thus apparent that relay 3-7AX is energized in a manner similar to relay 2-7AX and is retained energized by a stick circuit similar to that for relay 2-7AX. It is also desired to point out that relays 4-7AX and S-7AX are energized and retained energized by similar circuits and no detailed description of these l circuits is necessary;

By referring to Figures 2a and 2b it may be seen that the energization of relay 3-7AX completes a pick-up circuit for relay 3-7XPR. This circuit may be traced from battery terminal B through front contact c of relay 1 3-7AX, conductor Si, and winding of relay 3-'7XPR 12 to battery terminal N. Relay 3-7XPR is also provided with a stick circuit which may be traced from battery terminal B through back contact a of track relay 3-7TR, front contact a of relay 3-7XPR, and winding of relay 3-7XPR to battery terminal N.

The energization of relay 37XPR by the closing of front contact c of relay 3-7AX establishes a stick circuit to relay 3-7XPSR which may be traced from battery terminal B through front contact b of relay 3-7XPR, front contact a of relay 3-7XPSR, and winding of relay B-XiSR to battery terminal N. Relay 3-7XPSR is normally retained in an energized condition by a multiple control circuit which may be traced from battery terminal B through contact a of switch circuit controller 37SWC in its normal position or from battery terminal B through front contact a of relay 3-7TR and front contact b of relay 37APTR, and thence through conductor 60 to front contact a of relay 4-7APTR, conductor 61, and winding of relay 37XPSR to battery terminal N. Contacts a of relay 3-'7TR and switch circuit controller 37SWC also are used in a multiple stick circuit for relay 3-7XPSR. This circuit may be traced from battery terminal B through front contact a of relay 3-7TR or from battery terminal B through contact a of switch circuit controller 3-7SWC in its normal position and front contact b of relay 3-7APTR, and thence through front contact b of relay 3-7XPSR, and winding of relay 3-7XPSR to battery terminal N.

I will now assume that the third cut of cars enters 'track section 1-7T. This movement will cause the switch storages in storage bank 1-7A to be transferred to storage bank Z-7A if, at this time, the storage for the second cut of cars has been transferred to storage bank 3-7A by the entrance of the second cut into track section 2-7T. The third cut of cars being destined for track 7, relay 1-'7AX was never energized and, upon the transfer from storage bank 1-7A to storage bank 2-'7A of the storages for the third cut of cars, relay 2-7AX also remainsl deenergized.

l will now further assume that the second cut of cars enters track section 3-7APT and vacates track section 2-7T. No movement of switch 2-7SW will result upon the unlocking of that switch by the picking up of relay 27TR when the second cut of cars vacates track section 2-7T as the route for the third cut of cars is also through switch 2-7SW reverse. The entrance of the second cut of cars into track section 3-7APT deenergizes relay 3-7APTR which opens the control circuit to relay 27XPSR at contact cz of relay 3-7APTR. Upon vacating of the track section 2-'7T by the second cut, track relay Z-TR picks up opening its back contact a in the stick circuit to relay 2-7XPR and deenergizes that relay. However, the slow release feature of relay 27XPR retains that relay picked up for a short period of time and the stick circuit through its front contact b to relay 2- 7XPSR closed for a sufiicient period of time to bridge the transfer of contact a or" relay 2-7TR from its back to its front contact, and re-establish the stick circuit over that contact to relay 2e7XPSR. Relay 2-7XPSR is thus retained energized at this time and, after the effect of the slow release feature of relay 2i-7XPR has worn away, this latter relay drops.

As previously set forth relay 3-7XBSR is energized by several multiple circuits at this time. The deenergization of relay S-'APTR opened at its contact b the control circuit through contact a of relay 3-7TR and the stick circuit through contact a of switch controller 3-7SWC to relay ZJXPSR. However, relay 3-7XPSR is still energized by the stick circuit through contact b of relay 3- 7XPR, the stick circuit through contact a of relay 3-7TR and the control circuit through contact a of switch circuit controller 3-7SWC- Relay XR is thus still retained energized, and no crossing warning is as yet actuated.

When the second cut of cars enters track section'3-7T the route storage for that cut in storage bank 37A iS 13 cancelled and relay 3-7AX drops opening the Apick-'up circuit to relay 3-7XPR. However, the stick circuit to relay 3-7XPR through back contact a of relay 3-7TR is established and relay 3-7XPR remains energized. The stick circuit to relay 37XPSR through front contact b of relay 3-7XPR is thus maintained.

Assuming now that the third cut of cars enters track section Z-7T, the route storages in storage bank 2-7A are transferred to storage bank 3-7A. The route for this third cut of cars is over switch 3-7SW reverse but the switch storage cannot immediately take elect as switch 3-7SW is locked by the occupancy of track section 3-7T by the second cut of cars. Y

The entry of the third cut or" cars into track section 2-7T again deenergizes track relay 2-7TR. Normal contact a of switch circuit controller 2-7SWC has been open ever since switch 2-7SW was positioned reverse by the transfer of the route storage for the Second cut of cars into a storage bank 2-7A and the unlocking of that switch -by the iirst ont of cars vacating track section 2-7T.

The opening of front contacta of relay 2-7TR in the stick and control circuits of relay 2-7XPSR opens the last remaining energizing circuit for that latter relay and that relay drops. The opening of front contact c of relay ZJXPSR opens the previously traced control circuit to elay XR. Relay XR drops closing its back contact a and completes the circuit for actuation of the highway crossing warning devices. ylt is thus apparent that the entry of the third cut of cars into the approach warning track stretch causes actuation of the highway crossing warning devices, this third cut of cars being destined for storage track 7, the route to which leads over the highway crossing.

I will now assume that the second cut of cars vacates track section 3-7T thereby unlocking switch 3-7SW and allowing the switch to be positioned reverse by the switch storage for the third cut of cars. Assuming also that the third cut of cars enters track section 3-7APT and vacates track section 2-7T, relay 3-7APTR is deenergized and relay Z-TR picks up. Relay 2-7XPSR is not picked up by the closing of contact a of relay 2-7TR as the control circuit to relay 2-7XPSR is open at contact a of relay 3-7APTR. Relay XR therefore remains deenergized and the highway crossing warning devices continue to operate.

The entryv of the third cut of cars into track section 3-7T deenergizes relay 3-7XPSR by the opening of contact a of relay 3-7TR, contact a of switch circuit controller 3-7SWC already having opened upon switch 3- 7SWC being positioned reverse as described above. The vacating of track circuit 3-7APT by the third cut of cars allows contact a of relay 3-7APTR to close completing the pick-up circuit to relay 2-7XPSR and consequently closing the control circuit to relay XR at contact c of relay 2-7XPSR. However, contact c of relay 37XPSR having already opened, relay XR will remain deenergized and the crossing warning devices con tinue to operate.

As the third cut of cars proceeds towards storage track 7 track relays 4-7APTR, 4-7TR, 5-7APTR and 57TR will be deenergized in that order. Relay 3-7XPSR will be maintained deenergized by contacta of relay 4-7APTR until the cut enters track section 4-7T and vacates 4- 7APT R. The deenergization of track relay 4-7TR opens at'its contact a the vcontrol circuit to relay 4-7XPSR and deenergizes that relay to open the control circuit to relay XR at contact c of relay 4-7XPSR. The vacating of track section 47APT and subsequent closing of contact a of relay 4-7APTR `causes relay 3`7XPSR to pick up and close its front contact c in the control circuit of relay XR. Relay XR remains deenergized however due to contact c of relay 4-7XPSR being open.

The operation of relays -7APTR, 5-7TR and `5- 'XPSR as the cut of cars proceeds is similar to that is necessary. lIt is believed suiiicient topoint Aout that relay XR will remain deenergized by the deenerization of a relay with an XPSR sufiix until the cut of cars enters track section HXT. The entrance of the cut into track section HXT will deenergize relay HXT R and open at contact a of relay HXTR the control circuit to relay XR. The vacating of track section 5-7T will allow relay 5-7XPSR to pick up and, assuming that no other cut of cars destined for track 7 has entered the approach warning track stretch, all the XPSR relays will again be in their normally energized condition.

When the cut of cars enters track section HXT and deenergizes relay HXTR a pick-up circuit for directional stick relay ESR is completed. This circuit may be traced from battery terminal B through back contact b of relay HXTR, front contact b of relay APHXTR, back contact c of relay WSR and the winding of relay ESR to battery terminal N. After relay ESR is thus picked up a stick circuit is established from battery terminal B through back contact b of relay HXTR, front contact a of relay ESR, and the winding of relay ESR to battery terminal N.

Upon entering o fthe cut of cars into track section APHXT, relay APHXTR is deenergized and establishes another stick circuit to relay ESR. This circuit may be traced from battery terminal-B through back contact b of relay APHXTR, front contact a of relay ESR, and winding of relay ESR to battery terminal N. It is to be noted that relay ESR is provided with a slow release feature to prevent the dropping of that relay in the event `relay HXTR opens its back contact b before relay APHXTR closes its back contact b due to loss of track shunt from joint hopping when a car or cut of cars movesfrom track section HXT to'track section APHXT.

When the cut of cars vacates track section HXT relay HXTR will pick up and close its front contact a in the control circuit of relay XR. The previously described control circuit to relay XR will be open at contact a of relay APHXTR but another control circuit forenergizing relay XR will be established over front contact b of directional stick relay ESR. This circuit may be traced from battery terminal B through front contact b of relay ESR, front contact c of relay 2-iXPSR, front contact c of relay 3-'7XPSR, conductor kS5, front contact c of relay 4-7XPSR, front contact c of relay 5-7XPSR, conductor 57, front contact a of relay HXTR, and winding of relay XR to battery terminal N. Relay XR will, therefore, pick up after the cut of cars vacates track section HXT and remain picked up to prevent operation of the crossing warning devices while the cut is in track section APHXT and receding from the crossing. It is apparent from the previously traced stick circuit to relay ESR through back contact b of relay APHXTR that-relay ESR once being energized will remain so as long as track section APHXT is occupied by a cut of cars. The action of directional stick relay ESR is thus thesame as for similar relays in a conventionall highway crossing warning system.

I will now assume that a railroad vehicle such as a trimmer engine moves from storage track 7 towards the hump and into track section APHXT. The deenergization of relay APHXTR opens at its contact a the control circuit to relay XR and starts operation of the crossing warning devices. When the train enters track section HXTthe control circuit to relay XR will also be opened "at vcontact a of relay HXTR. The closing of back contact'c of relay HXTR will close a pick-up circuit to directional stick relay WSR. This circuit may be traced from battery terminal B through back Contact c of relay HXTR, conductor 65, front contact d of relay 57XPSR, front contact d of relay 4-7XPSR, conductor 67,l front contact d of relay 3-7XPSR, front contact dof relay 2-7XPSR, back contact c of relayfl-ESR, and winding of described above and no detailed operation of these relays relay WSR to battery terminalv N, 'Ille picking Pof 15 relay WSR and the closing of its front contact a establishes a stick circuit which is traced from battery terminal B through back contact c of relay HXTR, front contact a of relay WSR, and winding of relay WSR to battery terminal N.

The trimmer engine moving towards the hump must move through all of the switches 2-7SW, 3-7SW, 4J7SW and S-7SW in the reverse position and the hump operator so positions these switches by manipulation of the manual switch control levers on the control machine. The operation of these circuits form no part of my invention and are therefore not covered in detail. However, for purposes of this description, it may be assumed that these manual switch `control circuits operate similarly to those described in the previously mentioned copending application, Serial No. 592,198.

The reversal of switch 5-7SW as set forth above opens -the control circuit to relay 5-7XPSR at contact a of switch circuit controller 5-7SWC. This circuit may be traced from battery terminal B, through normal contact a of switch circuit controller 5-7SWC, and winding of relay 5-7XPSR to battery terminal N. Relay -7XPSR, however, remains energized by a control circuit which may be traced from battery terminal B, through front contact a of relay 5-7TR, back contact c of relay 5-7LRlPSR, front contact b of relay 5-7APTR and winding of relay 5-7XPSR to battery terminal N. Relay 5-7XPSR is also retained energized at this time by a stick circuit which may be traced from battery terminal B, through front contact a of relay 5-7TR, back contact c of relay 57LRPPSR, front contact a of relay 5-7XPSR, and winding of relay 57XPSR to battery terminal N.

When the trimmer engine moves through track section HXT and enters track section 5-7T, the last traced control and stick circuits to relay 5-7XPSR are opened at front contact a of relay 5-7TR. Relay 5-7XPSR is thus deenergized and opens its front contact c in the control circuit of relay XR. When the trimmer engine vacates track section HXT and relay HXTR closes its front contact a in the control circuit to relay XR, this latter relay is energized by a circuit which may be traced from battery terminal B through front Contact a of relay APHXTR, front contact b of directional stick relay WSR,

front contact a of relay HXT R, and winding of relay XR to battery terminal N. The deenergization of relay 57XPSR as traced above completed yanother stick circuit for relay WSR which is traced from battery terminal B through back contact d of relay S-7XPSR, conductor 65, front contact a of relay WSR, and winding of relay WSR to battery -terminal N. It is, therefore, apparent that the opening of the stick circuit to relay WSR through back contact c of relay HXTR when the trimmer engine vacates track section HXT has no eect on relay WSR. It should be pointed out that relay WSR, simi?V larly to relay ESR, is provided with a slow release feature to prevent that relay from opening its contact a in the event of joint hopping when the trimmer engine moves from track section HXT to track section 5-7T. This slow release feature is operative to retain relay WSR energized in the event the engine joint hops when moving from any track section to ,the next in its movement towards the hump.

Assuming now that the trimmer engine enters track section 5-7APT and vacates track section 5-7T, relay' 5-7XPSR remains deenergized as its control circuit remains open at contact b of relay 5J7APTR. The stick circuit to relay WSR through back contact d of relay S-'XPSR is maintained and relay XR remains energized by the previously traced circuit through front contact,

b of relay WSR. It is therefore apparent from the foregoing description that relay XR picks up when relay HXTR picks up upon the vacating of track section HXT by the trimmer engine, and the crossing warning devices are not operated as the' engine recedes from the cross le ing since the directional stick relay WSR is held up as the engine recedes.

The reversal of switch 4-7SW, by the manipulationof the manual switch control lever for that switch bythe operator as previously set forth, opens at contact a of switch circuit controller 4-7SWC the control circuit to relay 4-7XPSR- When the trimmer engine enters track section 4-7T and contact a of relay 4-'7TR opens, the multiple co'ntrol circuit and the stick circuit to relay 4-7XPSR are opened and that relay drops, opening at its contact c the normal control circuit to relay XR. However, the closing of back contact d of relay 4-7XPSR establishes another stick circuit to relay WSR and relay XR is thus retained energized by the previously traced control circuit through front contact b of relay WSR. This additional stick circuit to relay WSR may be traced from battery terminal B through back contact d of relay 4-7XPSR, and, assuming relay 5-7XPSR is now again energized the trimmer engine having vacated track section 5-7APT, front contact d of relay 5-7XPSR, conductor 65, front contact a of relay WSR, and winding of relay WSR tobattery terminal N.

Relay 4-7XPSR is maintained deenergized when the trimmer engine occupies track section 4-7APT by the opening of front contact b of relay 4-'7APTR in the control circuit to relay 4-7XPSR. It is apparent that relays 3-7XPSR and 2-7XPSR will operate in a similar manner as relays 5-7XPSR and 4-XPSR as the trimmer engine moves towards the hump, and that relay WSR will thus be retained in an energized condition and prevent operation of the highway crossing warning devices while the engine is receding from the crossing. No detail description of the operation of these circuits is, therefore, necessary.

In the control circuits of the relays 2-7XPSR, 3- 7XPSR, 4r-7XPSR and 5-7XPSR is a contact a of switch circuit controllers 2-7SWC, 3-7SWC, 4-7SWC and 5-7SWC, respectively. Each of these contacts is closed when the switch associated with each circuit controller is in its normal position. The circuits over these contacts a have previously been traced in connection with the operation of the automatic switching circuits but their true `function is in connection with manual switch control.

When the switches in the yard are being individually controlled by manipulation of the manual switch control levers, no track selection push buttons are operated and therefore no destination identities are being stored. Since the operator can position each Switch to one position or the other by the manipulation of its manual switch control lever at any time before a cut of cars enters the detector track section for each switch, it cannot be determined deiini-tely whether the cut will move over the crossing or will follow a route other than over the crossing, until a switch is positioned normal and locked so by the cut of cars entering the detector track section for that switch. Therefore, in order to assure that the crossing warning devices are in operation for a cut of cars moving toward the crossing and that the devices no longer operate after it is definitely determined that the out is to be diverted from the route over the crossing, the circuits are arranged as described below. This arrangement prevents unnecessary operation of the crossing warning devices.

I will iirst assume that a cut of cars is to move to storage track 2 `and switches l-7SW and 2-7SW are positioned normal by operation of the manual switch control levers. This positioning of switch 1-7SW is irnymaterial insofar as the following circuit description iS concerned, but, switch 2-7SW being positioned normal, contact a of switch circuit controller 2-7SWC in the control circuit of relay 2-7XPSR is closed. Therefore, when the aforementioned cut of cars enters the rst track Section 2-7T in the lapproach warning track stretch and relay -TR is deenergized, the opening of contact a of relay 2-7TR does not deenergize relay 2-'7XPSR and Ifa crossing warning is n-'ot initiated as the :control circuit `to'relay XR remains closedat contact c rof'relay 2-7XPSR.

Now assuming that la cuit of -cars Ais to move to storage track 3, switch l-7SW will remain in the normal position, switch 2-7SW will be positioned 'reverse and .switch 3-7SW will be :positioned normal by the manual `switch control levers. Contacta of switch `circuit controller 2-7SWC Will open when switch 2-7SW moves reverse and contacta of switch circuit controller 3-7SWC will remain closed. When the cut of 'cars enters track circuit 2-7T, relay 2-7TR will Aopen its front contact a and relay 2-7XPSR will drop, opening its front contact c in the control circuit of relay XR. This latter relay will also drop and close its back contact a in the control circuit of the crossing warning devices, causing them to operate. These devices 'will continue to operate until the cut of cars vacates track section 3-7APT, as contact a of relay 37APTR will keep open the control circuit to relay 27XPSR. It should be noted here that :since no destination identity for this cut of cars was stored, relay 2*-7XPR could not be energized to prevent deenergization of relay 27XPSR by establishing the stick circuit over contact b of relay 2-7XPR andcontact a of relay 2-7XPSR.

After the cut of oars vacates 3-7APT, relay 2-7XPSR will pick up, picking up relay XR and the crossing warning devices will stop operating. The entry of the cut of cars into track section 3-7T will not deenergize 3-7XPSR as that relay is retained energized by the con'- trol circuit through contact a of switch circuit controller -3-7SWC, similarly as 27XPSR was'retained energized when the previous cut of cars moved over switch 2-7SW in the normal position.

The circuits for operation of relays 4-7XPSR and 5-7XPSR, under conditions of manual control of the switches, are similar to those described above for relays 2-7XPSR and 3-7XPSR. Therefore, for a cut of cars destined for track 4, switches 2-7SW and 3-7SW being positioned reverse, contacts a of their respective switch circuit controllers 2-7SWC and 3-7SWC are open and relays 2-7XPSR and 3-7XPSR will be successively deenergized as the cut proceeds towards track 4; and the crossing warning devices will begin to operate when the cut enters track section 2-7T and will continue to operate until the cut vacates track section 4-'7APT, as front contact a of relay 4-7AP'1`R will keep open the control circuit to relay 3-7XPSR. Similarly, for a cut of cars destined for track 5, the devices will operate until the cut vacates track section 5-7APT since front contact a of relay 5-7APTR will keep open the control circuit to relay 4-7XPSR.

It is thus apparent that the operation of the highway crossing warning devices, under the condition of switch operation by manual control, is stopped at the earliest practicable time after it is` definitely determined that a cut of cars is not destined for track 7.

In the lower left-hand position of Fig. 2c, as previously stated, is shown in partial form the switch control circuits for switch 4-7SW. Only that portion of the circuits necessary for the purposes of this description are shown and the remainder of the circuits, represented by the dot dash lines at the left and right of this portion of the drawings, may be assumed to be the same as shown and described in the previously cited copending application Serial No. 592,198. The circuits shownr` in this portion of Fig. 2c are to provide for forced positioning` of switch 47SW to the normal position under the following described conditions.

Where a hand throw switch such as 5-6SWl diverges from a classification track (track 5) to an additional track (track 6) there may be some reason for not desiring any automatic switching moves to be made into the additional track or, in this instance over switch S-GSW in the reverse position. The reason, for example, may be that track 6 is not considered as a classification track, as t'- isits'ed' for' repair of cars Vor other purposes. Under these c A stances provision must "b'ejmade, insofar Aas '-it is possible, to prevent automatic switching moves through switch 5-7SW in the normal position whenever 'switch SLGSW is in the reverse position. It appears that the obvio'ts solution to this problem would rbe tofor'ce switch 5'-'7SW to the reverse position and lock it in that position when# ever switch '5-6SW is not in its normal position. How'- ever, if switch 5-6SW is positioned reverse by a person at the switch, when a cut of c'a'r's destined for classi'ca'tion track 5 is within the approach warning track stretch, no crossing warning has been initiated for the 'cut of cars and it is undesirable to route the cut to classification track 7 Without the proper crossing warning time. The cir'- cuits shown in the said portion of Fig. 2c are, therefore, for the purpose of re-routing a cut of cars, undern'the described condition, into classification track These circuits will so operate as long as the cut of cars hasnot entered track section 4-7T and lthereby locked switch 4-7SW in its reverse position. `If the cut has already occupied track section 47T at the times'vvitch 5-6S'W is positioned reverse, then the cut is allowed torprocefed to track 6, rather than be re-routed to track 7 without the proper crossing warning time. Y

I will now assume that a cut of cars having associated therewith a route identity for classification track 5 is -proceeding from the hump toward its destination. Referring to the said portion of Figp. 2c, there is shown the winding only of a relay 4-7A1. This relay lis a switch storage relay associated with storage bank 4 -7A and con'- trols switch 4-7SW. Relay 4;7A1 is energized to position switch 4`7SW reverse when theV route storage` for cut of cars is transferred into storage bank 4-7A. As previously pointed out the v"transfer of route storages'y is described in the aforementioned copending application, Serial No. 592,198 and forms no part of my inventioiiv.

Relay 4-7XPR will also be energized by the energi'z'atin' of 4-7AX, when the route storage for the cut is traitsferred into storage bank 4;7A since the destinationof the cut is storage track 5 and not over the highway. Under these conditions the energization of relay 4-7A1 Will complete a circuit to the reverse control magnet RM for switch 4'-7SW. Assuming that battery terminal B is cone nected to Contact q of relay 4-7A1 through the dot dash portion of the circuits shown, the circuit 'to control magnet RM may be traced from battery terminal B through front contact d of relay 4-7A'1, front Contact l of relay 4-7WP, contact a of switch circuit controller 5-6SWC in its normal position, front contact b of relay 4-7TR, winding of reverse switch control magnet RM, through the dot dash portion of the circuits 'to battery terminal N. All of the apparatus represented by the dot dash lines being assumed to be in proper position, vswitcll 4-7SW will move reverse, if not already so, for the route to storage track 5'.

I will now further assume that, after the cut of cars destined for storage track 5 has entered track section 2`-7T', track switch 5-6SW is positioned reverse by hand by someone at the switch. When the route storage forthe cut of cars is transferred into storage bank 4-7A`relays 4-7A1 and 4-7AX are energized and consequently, as previously decribed, relay 4-7XPR is Ienergized and a circuit is completed to the' normal switch control magnet NM rather than to the magnet RM as before. This circuit may be traced fromA battery terminal through front contact a of relay 4-7-7A1, front contacta of .relay 4-7WP, contact a of switch circuit controller 5-6ASYWC iti its reverse position, front contact c of relay 4-7XPR, front contact c of relay 4-7TR and the winding', of controlV magnet NM to battery terminal N. The switch will thus be positioned toy its normal position, if not already so, and the cut of cars will proceed to storage track 4 rather than track 6, as it would if the switch 4-7`SW is not forced positioned normal. g Y

I will new assume-'tirar a cut' cf ears, having associated .therewith a classification track 7 route identity, is moving from the hump and switch -6SW is in its reverse position. When the storage for this cut is transferred into storage bank 4-7A, relay 4-7A1 is energized but relay 4-7AX will remain deenergized as the cut is to move over the highway crossing. Relay 4-7XPR will, therefore, also remain deenergized. The energlzation of relay 4-7A1 completes a circuit to control switch 4-7SW to its reverse position for the route to storage track 7. This circuit may be traced from battery terminal B through front contact a of relay 4-7A1, front contact a of relay 4-7WP, contact a of switch circuit controller 5-6SWC in its reverse position, back contact c of relay 4-7XPR, front contact b of relay 4-7TR, and the winding of reverse control magnet RM to battery terminal N. Switcb 4-7SW is thus positioned reverse for the route to storage track 7. It is apparent from the circuits described that, when hand throw switch 5-6SW is in its reverse position and the route identity for a cut of cars destined for storage track 5 is transferred into storage -bank 4-7A, switch 4-7SW is forced positioned normal to cause the cut to move to storage track 4. However, when the route identity of a cut of cars destined for storage track 7 is transferred into storage bank 4-7A, the fact that switch 5-6SW is in its reverse position has no eect on the routing of the cut and switch 4-7SW is positioned reverse to allow the cut to proceed to storage track 7.

In the lower right-hand portion of Fig. 2c, as previously pointed out, is shown in partial form the switch control circuits for switch 5-7SW. Similarly as for switch 4-7SW, only that portion of the circuits necessary for vthe purposes of this description are shown and the remainder of the circuits are represented by the dot dash lines at the left and right of this portion of the drawings. There is also shown in this portion of Fig. 2c the winding only of a relay 5-7A1. This relay is a switch storage relay associated with storage bank 5-7A and controls switch 5-7SW similarly as relay 4-7A1 controls switch 4-7SW as previously set forth. Battery terminals B and N are shown at the ends of the dot dash lines for the purposes of tracing the circuits shown. It is assumed that the apparatus represented by the dot dash lines is properly positioned and that the battery is therefore connected to the solid line circuits shown and described below. The circuits shown in the said portion of Fig. 2c vare to provide for forced positioning of switch 5-7SW vto the normal position under the following described conditions. If a cut of cars enroute to track 1 is misrouted at switch 1-7SW or if switch 1-7SW is manually positioned normal for the cut of cars so that the cut may possibly proceed over the highway crossing, the crossing warning devices will begin operation when the cut enters track section Z-7T and will continue to operate as long as the cut is in any of the track sections in the approach warning track stretch. This is because no highway crossing destination identity was associated with the cut and, therefore, it is as if the cut were originally destined for storage track 7 or over the highway crossing. Even though such operation may cause unnecessary actuation of the crossing warning devices, the mis-routed cut perhaps actually proceeding to some track other than storage track 7, this type of operation is on the side of safety insofar as protection for the highway crossing is concerned.

I will assume that a cut of cars destined for storage track 4 is in the approach warning track stretch proceeding toward storage track 4 and, further, that this cut is mis-routed at switch 4-7SW through that switch reverse rather than normal as intended.- Such mis-routing can occur, for example, when a switch is prevented from moving from one position to the other by a physical obstruction in the switch. This cut of cars being originally destined for storage track 4 has associated therewith no switch storage for any switch beyond switch 4-7SW. Thus, when the cut is mis-routed at switch 4-7SW, the

switch storage relay 57A1 in storage bank 5-7A will remain deenergized, switch 5-7SW will be positioned normal, if not already so, and the cut of cars will proceed to storage track 5 and not over the highway crossing. The circuits for positioning switch 5-7SW normal under these conditions are the usual switch contro-l circuits. Referring particularly to Fig. 2c the circuits may be traced from battery terminal B through back contact a of switch storage relay 57A1, front contact b of relay 5-7WP, front contact c of relay 5-7TR and winding of normal control magnet NM for switch 5-7SW to battery terminal N.

In the yard track arrangement shown in Fig. l of the drawings, similar action as described above, will take place if a cut of cars is mis-routed at switches 27SW or 3-7SW. If a cut originally destined for storage track 2 is mis-routed at switch Z-7SW, the cut will proceed to track 3, there being no switch control storage for positioning switch 37SW reverse and the automatic switching system acting as if there were a storage for positioning switch 3-7SW normal. Similarly if a cut of cars originally destined for storage track 3 is mis-routed at switch 3-7SW, the cut will proceed to storage track 4 for the same reasons as described above. This circuit operation forms no part of my invention and is merely set forth for completeness of this description. More detailed action o-f the circuits under conditions of mis-routing as described above may be had by referring to the above identified copending application, Serial No. 592,198.

I will now assume, for example, that there may be an additional switch leading from classification track 4 into another classification track. Also that a cut of cars which is destined for this assumed track over the assumed additional switch in the reverse position is approaching switch 4-7SW and should, of course move through switch 4-7SW in the normal position in order to proceed to the assumed track through the assumed additional switch in the reverse position. However, switch 4-7SW being unable to move to the normal position due, for example, to a physical obstruction of the switch the cut of cars procceds through switch 4-7SW in the reverse position and is thus mis-routed. This cut retains its remaining route description in the system and will proceed in the vroute set up by this route description. The switch control storage in this route description calls for the assumed additional switch to be positioned reverse, and this switch control storage-will be lapplied to switch 5-7SW instead of to the assumed switch as intended. However, the cut of cars, being originally destined for a route other than over the highway crossing, also has associated therewith a destination identity and no start for the crossing warning devices was originated due to the energization of relays 2-7XPR, 3-7XPR and 4-7XPR as the cut proceeded through the approach warning track stretch. Relay 5-7XPR is thus also energized when the storages associated with the cut of cars is transferred into storage bank 5-7A. Switch storage relay 5-7A1 is also energized to control switch 5-7SW to its reverse position as pointed out above. It being impossible, under these conditions, to glve sufficient warning time to vehicles using the highway crossing, provisions are made for forced positioning switch 5-7SW to the normal position as described in the following paragraph.

Referring again to the lower right-hand portion of Fig. 2c the energization of rel-ay 5-7A1 completes a circuit for energization of reverse control magnet RM for switch S-7SW when relay 5-7XPR is in its deenergized condition. This circuit will be completed when a cut of cars is routed to storage track 7 under normal conditions and may be traced from battery terminal B through front contact a of relay 5-7A1, front contact a of relay 5-7WP, front contact b of relay 5-7TR, back contact c of relay 5-7XPR and winding of reverse control magnet RM to battery terminal N. Magnet RM is thus energized and switch 5-7SW positioned reverse foiga gastheer i'nove to track 7. When, however, relays' S-7XPR and -7A1 are energized due to mis-routing as described above, the control circuit for switch 5-7SW is traced from battery terminal B through front contact a of relay 5-7A1, front contact a of relay 5-7WP, front contact b of relay 5-7TR, front contact c of relay 5-7XPR, back contact b of relay 5-7LRPPSR, and winding of normal switch control magnet NM to battery terminal N. (The back contact b of relay 5-7LRPPSR has no function at this time but its use will be described later on.) Thus, magnet NM is energized, switch 5-7SW is positioned normal and the mis-routed cut of cars is routed to storage track 5, rather than over the highway crossing to storage track 7 without the proper operating time of the crossing warning devices.

Fig. 2c also shows a contact a' of manual switch control lever 5-7MC. This control lever is used for manual control of the switch to either normal or reverse positions but only the reverse switch control circuit through contact a in the reverse position is needed to be shown for purposes of this description. The circuit shown is identical to the usual manual reverse switch control circuits used and the other circuits controlled by the lever may be assumed to be as covered in the copendlng application, Serial No. 592,198, referred to hereinbefore.

I will now assume that a cut of cars is proceeding from the hump to storage track 5 under control of the automatic switch control system. Under these conditions switch 5-7SW is to be positioned normal. I will further assume that, previous to the arrival of the cut at switch 5-7SW, the operator moves the manual switch control lever 5-7MC to its reverse position and thus supercedes the automatic control for positioning switch 5-7SW to its norm-al position. The cut of cars, being originally des-tined for track 5, has associated with it a destination identity and relay 5-7XPR will be energized upon the storages for the cut being transferred into storage bank 5-7A. If the manual switch control lever is manipulated to its reverse position before the said storage transfer is made into storage bank 5-7A, switch 5-7SW will be positioned reverse by a circuit which may be traced from battery terminal B through contact a of manual switch control lever 5-7MC in its reverse position, front contact b of relay 5-7TR, back contact c of relay 5-7XPR and the winding of switch 5-7SW reverse control magnet RM to battery terminal N. However, when the aforesaid transfer of storages is made into storage bank 5-7A, relay 5-7XPR will be energized as stated and a control circuit will be completed to posi-tion switch S-7SW normal. This circuit may be traced from battery terminal B through contact a of manual switch control lever 5-7MC in its reverse position, front contact b of relay 5-7TR, front contact c of relay 5-7XPR, back contact b of relay 5-7LRPPSR to normal control magnet NM of switch 5-7SW. Switch 5-7SW will thus be positioned normal and the cut of cars will proceed to storage track 5 as originally intended. It may thus be readily understood that, since no actuation of the crossing warning devices would be initiated for a cut of cars destined for storage track 5, provision is made to prevent re-routing of the cut to storage track 7 by the operators manipulation of manual switch control lever 5-7MC to its reverse position.

One additio-nal feature of the circuits remains to be described. This is a so-called anti-corner'ing feature and is related to the above-described circuit operation.

At approximately the center right-hand portion of Fig. 2c is shown a relay 5-7LRPPSR. This relay is con- Itrolled by a circuit which includes contact b of manual switch control lever 5-7MC which is closed when the lever is in its reverse` position, and back contacts d' of relays WSR' and HXTR. In addition a stick circuit for relay 5-7LRPPSR is provided which includes its own front contact a, back contact c of relay 5-7APTR and said'contact bv of manual control lever 5-7MC. Contacts 22 by and c of relay S-7LRPPSR are used inthe previously described control circuits for switch 5-7SWl and relay 5-7XPSR, respectively.

lf a cut of cars moving tov storage track 7 is stopped or is moving slowly through track section HXT, it may possibly be fouling? trac'k 5 lead. That is,vthe cut may not have advanced sufliciently beyond track section 5-7T to allow clearance for a second cut of cars to move through switch 5-7SW in the normal position to storage track 5. Under these conditions the operator would de= 'sire to prevent the cornering' of the second cut of cars, and to couple the second cut to the first cu't and allow both cuts to proceed to storage track 7. In the' circuits previously described it was shown how re-routing to storage track 7 of a cut of cars destined for storage track 5 is prevented if the operator manually manipu-l lates manual switch control lever S=7MC to the reverse position to attempt to re-route the cutto storage track 7. As set forth such re-routing is prevented because the highway. crossing warning devices are not operating for the cut of cars. However, if a lirst cut of cars is already proceeding to storage track 7, a crossing warning is operating for the first cut and no harm results from also alowing the second cut to proceed to storage track 7. Relief from the above described prevention of re' routing is therefore, provided under these conditions.-

Under the above circumstances, the operator moves manual switch control lever 5-7MC to its reverse position and relay 5-7LRPPSR is energized by a circuit which may be traced from battery terminal B through contact b of manual switch control lever 5"-7MC in its reverse position, conductor 70, back contact d of relay WSR, back contact d of relay HXTR, conductor 71 and the winding of relay 5-7LRPPSR to battery terminal N. The back Contact d of relay HXTR checksA the occupancy of track section HXT by the rst cut of cars, and the back contact d of relay WSR assures that this cut was' originally routed toward storage track 7 and that relay HXTR is not deenergized due to a trimmer engine occupying track section HXT and moving toward the hump.

The control circuit for switch 5-7SW may now be traced from battery terminal B through contact a of manual switch control lever 5-7MC in its reverse posi'- tion, front contact. b of relay 5-7TR, front contact c' of relay 5-7XPR (assuming that the storages for the second cut. of cars have been transferred into 5-7A storage bank) front contact b of relay 5-7LRPPSR and the winding of switch 5-7SW reverse control magnet RM to battery terminal N. It is thus seen that switch 5-7SW is permitted to be positioned reverse at this time by operation of its manual control lever 5-7MC.

The energization of relay 5-7LRPPSR establishes a stick circuit for that relay which may be traced from battery terminal B through contact b of manual switch control lever 5-7MC in its reverseV position, back contact c of relay 5-7APTR, front contact a of relay S-7LRPPSR and the winding of relay 5-7LRPPSR to battery terminal N.

The inclusion of back contact d of relay HXTR in the energizing circuit for relay 5-7LRPPSR checks that the crossing warning devices are operatingN before relay 5-7LRPPSR is picked up. This cheek having" been made, the energization of relay 5L7LRPPSR as described above opens at back contact c of relay 5-7LRPPSR the controlv circuit to relay 5-*7XPSR and deenergize's that relay. This deenergiz'ation of relay 5-'7XPSR= insuresY thatl the crossing warning. devices will. continuetoloperate as long as relay 5-7LRPPSRv is energized and switch` 5-7SW is positioned reverse. The stick circuit for relay 5'- 7LRPPSR through back contact c of relay 57APTR is employed to` retain relay 5-7LRPPSR energized: when the second cut of cars occupies track section- 5-7APT. Relay' S-7LRPPSR is thus retained picked up so that, if the rst cut ofcars vacates track section HX before the" second c'ut occupies track section 5-7T, relay -7LRPPSR will maintain relay 5-7XPSR in deenergized condition. After the second cut of cars enters track section 5-7T, relay 5-7XPSR will be maintained deenergized by the opening of its control circuit at front contact a of relay 5-7TR. If the second cut consists of but one car, relay 5-7LRPPSR will be deenergized when this cut vacates track section 5-7APT and occupies track section 5-7T solely. However, if manual switch control lever 5-7MC remains in the reverse position or has been moved from its reverse position but is again moved to that position, the entrance of the second cut into track section HXT will again energize relay 5 7LRPPSR and the circuits may operate for a third cut of cars similarly as they operated for the second cut.

It will be apparent that while in the foregoing description I have described operation of the system for only a few cuts of cars moving from the hump toward but a few storage tracks, the operation of the system for numerous cuts proceeding from the hump to their selected tracks will be similar.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

l. In a classification yard comprising a lead track connected through a plurality of switches to a plurality of classification tracks and provided with an automatic switch control system in which route identities, cornprising switch control storages for aligning routes for cuts of cars moving to the classification tracks, are established by track selecting means and are transferred to a route storage unit for the initial switch in said yard, and said system including a route storage unit for each switch in said yard and transfer means operating when a cut of cars traverses each switch for transferring the switch control storages for said cut to the storage unit for the switch next in advance along said route; in combination, a destination identity relay included in each route storage unit for each switch in the route to a predetermined classification track in said yard, means controlled by said track selecting means for energizing the destination identity relay included in the route storage unit for the initial switch in said yard when a classification track selected by said track selection means is a cassification `track other than said predetermined classification track, means controlled by said transfer means for energizing `the. destination identity relay included in each route lstorage unit for each next switch in the route to said predetermined classification track when the switch control storages contained in the unit for the preceding switch are transferred to the unit for said next switch, a Ahighway crossing said predetermined classification track, a crossing warning system for said highway, an approach warning track stretch in said route to said predetermined classification track and comprising a series of means for detecting track occupancy, and means controlled by -said track occupancy detection means and said destination identity relays for controlling said crossing warning system to provide a warning when said detection means ,detect a condition of track occupancy and said destination description relays are deenergized.

2. In a railway car classification yard comprising a .lead track connected through a plurality of track switches to a plurality of classiiication tracks and provided with an automatic switch control system comprising switch control storages for cuts of cars moving to the classifi- -cation tracks, said said system including a route storage unit for each track switch in said yard and trans- -Ifer means: operating when a cut of cars traverses each switch for transferring the switch control storages for aligning the route for said cut to the storage unit for j'the switch next in advance along said route; in combination, a highway crossing at least one classification track in said yard, a warning system for said highway, a crossing warning relay for said warning system, an approach. warning track stretch for said highway comprising a series of track sections each provided with a track circuit including a track relay, at least one destination identity relay included in each route storage unit for each track switch located within the approach to said highway, means controlled by said transfer means for energizing at least one of said destination identity relays when a storage for a route other than over said highway is stored in one of said storage units, and means controlled by said destination identity relays and said track relays for controlling said crossing warning relay.

3. In a railway car classification yard comprising a lead track connected through a plurality of track switches to a purality of classification tracks and provided with an automatic switch control system comprising switch control storages for cuts of cars moving to the classification tracks, said system including a route storage bank for each track switch in said yard and transfer means operating when a cut of cars traverses each switch for transferring the switch control storages for aligning the route for said cut to the storage bank for the switch next in advance along said route; in combination, a highway crossing at least one track in said clasification yard, an approach warning track stretch for said highway com prising a series of track circuits each including a track relay; a destination description relay associated with each storage bank associated with a track switch located in said approach warning track stretch, means controlled by said transfer means for energizing each destination description relay only when its associated storage bank contains a storage for controlling the associated track switch to a position which leads to a route other than over said highway, a control relay associated with each destination description relay, means controlled by each destination description relay for energizing its associated control relay when that destination description relay is energized, a crossing warning relay, and means for controlling said crossing warning relay controlled by contacts of said control relays and said track relays.

4. In a railway car classification yard comprising a lead track connected through a plurality of track switches to a plurality of classification tracks and provided with an automatic switch control system comprising switch control storages for cuts of cars moving to the classiiication tracks, said system including a route storage unit for each track switch in said yard and transfer means operating when a cut of cars traverses each switch for transferring the switch control storages for aligning the route for said cut to the storage unit for the switch next in advance along said route; in combination, a highway crossing at least one classification track in said yard, a series of track sections in approach to said highway each provided with a track circuit including a track relay, a destination identity relay included in each storage unit for each track switch located within the approach to said highway, means controlled by said transfer means for controlling said destination identity relays, a repeater relay associated with each destination identity relay, means controlled by each destination identity relay for controlling its associated repeater relay, a repeater stick relay associated with each repeater relay, means controlled by each repeater relay and at least one of said track relays for controlling the associated repeater stick relay, a crossing warning relay, means controlled by said repeater stick relays for controlling said crossing warning relay, a warning system for said highway, and means controlled by said crossing warning relay for controlling said warning system.

5. ln a railway car classification yard comprising a lead track connected through a plurality of track switches to a plurality of classification tracks and provided with an automatic switch control system comprising switch v QQntr'Ol storages ,for cuts of ca rfs .moving to the .clssiicagtion tracks, said system including a route storage unit A`for each track switch in said yard and transfer means operating when a cut of cars traverses each switch for transferring the switch control storages for aligning the route for said cut to the storage unit for the switch next in advance along said route; in combination, a highway crossing at least one classification track in said yard, an approach warning track stretch in approach to said highway and consisting of a series of track sections each provided with a track circuit including a track relay, va normally deenergized destination identity relay included in each storage unit associated with a track switch located in approach to said highway, means ,controlled by said transfer means for energizing said destination identity relays when their respective storageunits contain a storage for a route other `than across said highway, a normally deenergized repeater relay associated with each destination identity relay, means controlled by each destination identity relay for energizing its associated repeater relay when the destination identity relay is energized, a normally energized repeater stick relay associated with each repeater relay, means comprising a front contact of at least one of said track relays and a stick circuit including a front contact of each repeater relay for controlling its associated repeater stick relay, a normally energized crossing warning relay, means controlled by front contacts of all of said repeater stick relays for controlling said crossing warning relay, a highway crossing warning system for said highway, and means controlled by a back contact of said crossing warning relay for controlling said crossing warning system.

6. In a railway car classification yard comprising an entrance track connected through a plurality of track switches to a plurality of classification tracks and provided with an automatic switch control system comprising switch control storages for cars moving to the classification tracks, said system including a route storage unit for each track switch in said yard and transfer means operating when a cut of cars traverses each respective switch for transferring the switch control storages for aligning the route for said cut to the storage unit for the switch next in advance along said route; in combination, a highway crossing at least one classification track in said yard; a detector track section for each switch in said yard, each track section being provided with a track circuit including a track relay; an approach warning track stretch in approach to said highway; an approach track section between each detector track section located in said approach warning track stretch, each approach track section being provided with a track circuit including a track relay; a plurality of destination description relays each having a first position and a second position, one of said destination description relays being associated with each storage unit associated with a track switch located in approach to said highway; means controlled by said transfer means for controlling each destination description relay to its second position only when its associated storage unit contains a switch control storage for controlling the associated track switch to a position for a route other than across said highway; a plurality of repeater relays each having a first position and a second position, one associated with each storage unit associated with a track switch located within said approach warning track stretch; means controlled by said destination description relays for controlling each repeater relay to its second position when its associated destination description relay occupies its second position; a plurality of repeater stick relays each having a first position and a second position, one associated with each repeater relay, track switch, detector track relay and approach track relay; means controlled by said repeater relays for controlling each repeater stick relay to its second position when its associated repeater relay occupies its first position, its associated detector track relay or approach' track' relay reflects a condition of'track'occnpaney and vits associatedY track switch is in a position leading to a route over' said highway; a crossing Warning relay having a first positionr and a second position, means controlled by said repeater stick relays for controlling said crossing warning relay to said second position when one or more of said repeater stick relays occupy their second position due to occupancy of said approach warning track stretch by a railway car moving toward said highway, a crossing warning system, and means controlledl by said crossing warning relay for' controlling' said crossing warning system to provide a warning when the crossing warning relay occupies its second position.

7. ln a highway crossing warning system for a highway traversingrat least one classification track in a railway car classification yard, said yard comprising a lead track connected through a plurality of t'r'ack switches' to a plurality of classication tracks, and said yard provided with an automatic switch control system comprising switch control storages for cuts of cars moving tothe classification tracks, said system including a route storage unit for each track switch in said yard and transfer means operating when a cut of cars traversesV each switch for transferring the switch control storages for aligning the route for said cut to the storage unit for the switch nekt in advance along said route; in combination, an'approach warning track stretch in approach to said highway, atleast one track section associated with each track switch located within said approach warning track stretch, a track circuit for each track section each including a track relay, a destination identity relay associated with each track switch located within said ap proach warning track stretch, means controlled by said transfer means for controlling each destination identity relay; and control means for controlling said highway crossing warning system controlled by said track relay and said destination identity relays, said control means operating to provide a warning only when a railway car having associated therewith a preselected route over said crossing is present in said approach warning track stretch.

8. In a railway car classification yard comprisingta lead track connected through a plurality of track switches to a plurality of classification tracks and provided with an automatic switch control system including a route storage unit for each track switch in said yard, each unit including transfer means operating when a cut of cars traverses the associated switch for transferring the preselected switch control storages for aligning the route for said cut to the storage unit for the switch next in advance along said route; in combination, a normally deenergized destination identity relay for each storage unit for each track switch controlling the route to a predetermined one of said classification tracks, means controlled by said transfer means for energizing each destination identity relay only when its associated storage unit contains a switch control storage for controlling its associated track switch to a position other than for said route to said predetermined one of said classification tracks, a highway crossing warning system for a highway crossing said predetermined track, and means controlled by said destination identity relays for controlling said highway crossing warning system, said system operating only when the identity relays are deenergized and a cut of cars is progressing through said yard towards said highway.

9. In a railway car classification yard comprising a lead track connected through a plurality of track switches to a plurality of classification tracks and provided with an automatic switch control system comprising switch control storages for cuts of cars moving to the classificaton tracks, said system including a route storage unit for each track switch in said yard and transfer means in each storage unit operating when a cut of cars traverses the respective switch for transferring the switch control storages for aligning the route. for ,said cut to the storage unit for the switch next in advance along said route; in combination, a series of destination identity relays, means for energizing the lirst of said series of relays when a route to other than a predetermined classification track is selected for a cut of cars entering said yard, means controlled by said transfer means for energizing the other relays of said series in succession as said cut of cars progresses from track switch to track switch in its selected route, a highway crossing said predetermined classiiication track, a normally non-operating warning system for said highway; an approach control track stretch for said warning system, said stretch including a portion of the selected route for said cutof cars; and means controlled by front contacts of said destination identity relays for maintaining said warning system non-operating when said cut of cars occupies the portion of its selected route included in said approach control track stretch. V

10. In a railway car classification yard comprising a lead track connected through a plurality of power operated track switches to a plurality of classiication tracks and provided with an automatic switch control sytem comprising switch control storages for cuts of cars moving to the classiication tracks, said system including a route storage unit for each track switch in said yard and transfer means operating when a cut of cars traverses each switch for transferring the switch control storages for aligning the route for said cut to the storage unit for the switch next in advance along said route; in combination, a hand-throw switch leading from one classification track in said yard to a track other than a classificaton track when said hand-throw switch is in its reverse position, a series of destination identity relays one for each power operated track switch in the route to said one classification track, means for energizing the first of said series of relays when a route to said one classication track is selected for a cut of cars entering said yard, means controlled by said transfer means for energizing the other relays of said series in succession as said cut of cars progresses from track switch to track switch in its selected route, and means controlled by the destination identity relay for one of the switches beyond the switch .first preceding said handthrow switch and by said hand-throw switch for con trolling said automatic switch control system to control said one switch to a position leading to a classification track other than said one classification track when said hand-throw switch is in its reverse position.

References Cited in the tile of this patent UNITED STATES PATENTS 2,370,704 Allen Mar. 6, 1945 2,681,985 Claus June 22, 1954 2,700,728 Brixner Jan. 25, 1955 

